The U.S. Fifth Fleet opened a significant new front in the Pacific war with the invasion of the Japanese-occupied Gilbert Islands in eastern Micronesia on 20 November 1943. Vice Admiral Raymond Spruance, commanding the fleet from the heavy cruiser USS Indianapolis (CA-35), launched Operation Galvanic with simultaneous amphibious assaults against Makin and Tarawa, two coral atolls lying 93 miles apart, slightly north of the equator. Tarawa, gateway to the fortified bomber strip on Betio Island, was the strategic prize. With Betio in U.S. hands, the airfield would bring the Marshall Islands, 550 miles to the west, within range of heavy bombers and reconnaissance aircraft of the Seventh Air Force.
The capture of Betio and Tarawa Atoll was the mission of the Southern Attack Force, commanded by Rear Admiral Harry Hill, and its landing force, the 25,000-man 2d Marine Division, commanded by Major General Julian Smith. Both men knew they faced a well-led, well-armed force of several thousand rikusentai, Japanese Special Naval Landing Forces. They also knew they would have to breech Betio's coral reef at low tide.
The proximity of the Japanese Combined Fleet in the eastern Carolines was a primary concern. Admiral Chester Nimitz, commander-in-chief of the Pacific Fleet, ordered Spruance to "get the hell in and get the hell out" to avoid getting trapped in shallow waters by an enemy counterattack. Timing was also critical. Nimitz grimly reminded Spruance that Tarawa represented a tough but brief stepping-stone for the pending campaign against the more strategically valuable Marshall Islands, slated to begin eight weeks later. The operational tempo was so taut that Spruance could not postpone D-day in the Gilberts even a week in order to gain a more favorable tidal range.
The hurried Betio landing would thus become a storming operation—a frontal assault against a heavily defended island in broad daylight during a dangerously low tide. Success would depend on surprise, simplicity, fire-support coordination, and speed of execution—difficult objectives to attain by even the most experienced amphibious forces. Very few ship captains or troop leaders in the Southern Attack Force had any previous experience in conducting an assault from the sea against a strongly defended beach. Tarawa would provide a bloody proving ground.
Artful surprise and sheer grit enabled the initial U.S. assault waves to gain a foothold on Betio's northwest shore on D-day morning, but the advantage proved temporary. Intense Japanese fire and a freakishly persistent low tide prevented the build-up of firepower and reinforcements ashore. Casualties mounted, communications failed, and chaos ruled the beachheads. The few fragmentary radio reports to reach Hill's flagship described stark conditions ashore. "Have landed," one message reported. "Unusually heavy opposition. Casualties 70 percent. Can't hold." Another message came from the epicenter of the fighting on Red Beach Two: "We need help; situation bad." Hill and Smith sent an urgent message to their common superior, Rear Admiral Richmond Kelly Turner, the Fifth Amphibious Force commander at sea near Makin, requesting commitment of the force reserve, the 6th Marines, to Betio, adding, "Issue in doubt."1
The chilling words resonated throughout the chain of command. Desperate U.S. defenders of Wake Island, facing the Japanese landing on 23 December 1941, had signaled "Issue in doubt" in their final radio message. Alarmed, Turner authorized the return of the 6th Marines to the control of the 2d Marine Division.
There was more at stake for the Pacific Fleet in Operation Galvanic than possession of the Betio bomber strip. Defeat at Tarawa would indefinitely derail the promising new U.S. drive through the Central Pacific. Failure of the landing force to seize Betio Island would also discredit the unproven operational doctrine of forcible assault against strongly defended islands.
Tarawa in the Pacific War
The battle for Tarawa represented a crucial crossroads in the Pacific war. Twenty-three months had elapsed since Pearl Harbor; 17 since Midway. Although the Allies had seized the offensive from the Japanese in January 1943 with difficult victories at Guadalcanal in the Solomons and Buna, New Guinea, they experienced frustrating delays in generating their own offensive momentum. The Allies recaptured the Aleutians in 1943, but their subsequent amphibious campaigns bogged down in the thick jungles of New Georgia and Bougainville. The Japanese regional strongpoint at Rabaul, New Britain, continued to be an unassailable thorn in their side.
The senior officers responsible for waging war against Japan in 1943 faced serious limitations. The Allies had agreed from the beginning that the defeat of Adolf Hitler's Nazi Germany would constitute their primary strategic objective. Although the Combined (U.S. and British) Chiefs of Staff had postponed the long-anticipated cross-Channel assault against Fortress Europe until June 1944, preparations for Operation Overlord still demanded top priority for troops, planes, ships, and landing craft. The Pacific remained a backwater theater, whose few offensive campaigns had been limited in scope and scale.
Admiral Ernest King, representing the U.S. Navy on the Joint Chiefs of Staff (JCS), argued for greater offensive pressure against the Japanese by means of a second front through the Central Pacific. An outspoken advocate of sea power, King believed that the Central Pacific represented the royal road to Tokyo and the U.S. Navy should take the lead in such a maritime strategy. Yet King also insisted that the new front could be undertaken without drawing down European-theater assets by using the troops and shipping already available in the Pacific. At the Trident Conference in Washington in May, the Combined Chiefs accepted the U.S. "Strategic Plan for the Defeat of Japan," which included King's proposed Central Pacific drive.2
The new strategy elicited different reactions from the two U.S. theater commanders in the Pacific. Admiral Nimitz, whose realm included enormous oceanic areas dotted with widely scattered small islands, welcomed the concept of his Pacific Fleet attacking west in parallel to General Douglas MacArthur's route through New Guinea and the Philippines. General MacArthur, whose South-West Pacific Area featured narrow seas and large islands, strongly opposed what he perceived to be a wasteful duplication of effort. He argued for a single, concentrated drive to the Philippines under his sole command, fully supported by nearby land-based air and, as needed, by Nimitz's Pacific Fleet. King, however, backed Nimitz, prompting MacArthur's strident warning that the Central Pacific's lack of advance fleet bases and airfields would result in catastrophic defeat-a "reverse Midway."3
Proponents of the Central Pacific drive used the verb "whipsaw" to describe the effect of alternating offensives against the Japanese in the Southwest Pacific and the Central Pacific. In time, with MacArthur steadily advancing up the long coast of New Guinea toward the Philippines and Nimitz attacking through the Marshalls, Marianas, and Palaus, the whipsaw effect would prove its value. The alternating sequence of the U.S. landings at Bougainville, Tarawa, Cape Gloucester, and Kwajalein—within a period of exactly three months—proved the wisdom of this strategy.
The Initial Target
Nimitz and Spruance believed that the Marshall Islands were too far away and too unknown to be the first objective of the Central Pacific campaign. Commanders of the 1942-43 landings at Guadalcanal, North Africa, and the Aleutians each had reported the critical need for advance aerial photography of the beaches and inland objectives. Taking advance aerial photos of remote objectives seemed a common-sense preliminary measure, but here, too, the vast Pacific posed vexing problems.
In 1943, existing aerial cameras were still too bulky to fit in carrier-based fighters. In fact, only a bomber the size of the four-engine B-24 Liberator had the capacity and range to collect aerial photographs in the Central Pacific. Seventh Air Force Liberators based in the Ellice Islands could reach the Gilberts, but not the Marshalls. Betio's bomber strip thus became the imperative objective. On 20 July the Joint Chiefs agreed to Nimitz's recommendation that the Gilberts supplant the Marshalls for the opening campaign.
The Joint Chiefs had other pressing concerns about the Central Pacific. Only a few islands in the vast region seemed suitable for airfields or fleet anchorages, and the Japanese, anticipating that any Allied advance would target such objectives, were busily fortifying them. In addition, the coral reefs surrounding most of these strategic islands further complicated amphibious campaign planning. There would be no "cake-walk" landings like those at Kiska or the Russells that had occurred earlier in the year.
Learning from early intelligence reports that the Japanese were fortifying Tarawa Atoll, the Joint Planning Staff advised the Joint Chiefs to undertake the Gilberts campaign with "battle-tested shock troops with amphibious training."4 Three U.S. divisions in the Pacific met these qualifications in late 1943: the 7th Army Division, veterans of the Aleutians and already earmarked for the Marshalls; and the 1st and 2d Marine Divisions, veterans of Guadalcanal, both currently under General MacArthur's command. With MacArthur preparing for a major amphibious assault of his own against New Britain barely a month after D-day at Tarawa, the JCS compromised, leaving the 1st Marine Division with MacArthur and transferring the 2d Marine Division to Nimitz for the Gilberts assault.
In preparation for the Gilberts, Nimitz chose Spruance to command the newly constituted Fifth Fleet and two countervailing firebrands, Admiral Kelly Turner and Marine Major General Holland "Howlin' Mad" Smith to command the Fifth Amphibious Force and the expeditionary troops of the V Amphibious Corps, respectively.
Lean and Fat Years in the Pacific
The United States fought two wars in the Pacific, a consequence of the strategic priority accorded to the defeat of Germany combined with America's material unpreparedness to wage a two-ocean war in 1941. The first half of the Pacific war featured bare-boned resources, limited offensives, and hit-and-run raids, all conducted under the threat of the Japanese Combined Fleet. The second phase, beginning in late November 1943, finally reflected America's attainment of full wartime production, a tardy but awesome industrial transformation. One herald of this infusion of resources occurred with the arrival of the first Essex-class fleet carriers at Pearl Harbor.
Aircraft carriers were invaluable in the Pacific war. While vulnerable to land-based air attacks from nearby enemy airfields in the constricted waters of the Mediterranean and the North Sea, the carriers proved ideal for the vast expanses of the Pacific. Nimitz fought the first two years with no more than four carriers—sometimes as few as two—but in the war's second phase, the Pacific Fleet would include more than 100 flattops, many of them the highly capable Essex carriers.
Rear Admiral Charles Pownall would deploy six of these ships as the cutting edge of his Task Force 50 at Tarawa. Escorted by new high-speed battleships and logistic support ships, Pownall's carrier task forces could challenge the Japanese Combined Fleet for command of the seas. More than any other naval factor, the newly created Task Force 50 (soon to become Vice Admiral Marc Mitscher's Task Force 58) would make possible Spruance's stirring victories in the Gilberts, Marshalls, and Marianas.
A Residual Weak Link
Even though U.S. armed forces had adopted the concept of amphibious assault from the sea in the 1930s, Tarawa represented the first critical test of the doctrine against a heavily fortified island. The complex mix of sea-air-land and logistics components inherent in amphibious warfare required four supporting developments in order to become an operational capability: doctrine, organization, material, and training.
The new doctrine, promising but still unproven, was in place. The Navy and Marines also had made significant progress in organizing forces to support the amphibious mission, beginning with the historically thorny issue of unity of command. At Tarawa, Admiral Hill would command all forces until the third evening, when General Julian Smith could assume on-shore command of the 2d Marine Division.
Hill's force was configured for island assault, including task groups of older battleships and small escort carriers that would shell and bomb Betio Island, as well as boat groups and control craft to direct the ship-to-shore assault. In addition to three regimental landing teams, General Smith's division included specialized amphibious units, such as shore fire control teams, combat engineers, an amphibian tractor battalion, a cargo-handling shore party, and a battalion of naval construction troops (Seabees). In retrospect, the task organization for the Southern Attack Force lacked only one significant component: an underwater demolition team, which was not yet available in the Central Pacific.
With all of the progress, material shortfalls nevertheless continued to plague amphibious effectiveness. The Navy-Marine team lacked a suitable amphibious-force command ship in November 1943. The battleship USS Maryland (BB-46), a repaired survivor of Pearl Harbor, would prove unsuitable as a flagship for a division-level amphibious assault of Tarawa. Each thunderous salvo of her 16-inch guns would disable scores of landing-force radio circuits. On D-day, a frustrated Colonel David Shoup, commanding the assault forces ashore, would be forced to resort to the same means of communicating with his division commander as the Athenians used in the Peloponnesian Wars—sending messengers through the surf and out to the fleet. The lack of waterproof radios in the landing craft further compounded the critical communication failures between Marine commanders, both ashore and afloat. Nor could Shoup communicate with the carrier-based fighters strafing overhead.
Faulty communications in an operation so acutely dependent on timing, coordination, and swift adaptability contributed significantly to the "Issue in doubt" report on D-day at Tarawa. Yet there were even more critical material shortfalls in the ship-to-shore assault. The Pacific Fleet still lacked sufficient numbers of specialized amphibious ships and reef-crossing landing craft.
The Joint Chiefs and most senior Navy and Marine commanders involved in planning the Pacific war knew six months in advance that Betio Island's fringing reef and erratic tides would present a formidable barrier to Higgins boats, the most common U.S. landing craft; they required a minimum clearance of four feet of water to traverse a reef. Seeking a practical solution with assets at hand, the Marines proposed to convert their logistic support vehicles—tracked landing vehicles variously known as LVTs, amphibian tractors, or Alligators—into assault vehicles, using their tracks to clamber over reefs, their low centers of gravity to survive high surf, and their sizeable cargo bays to transport 15 to 20 combat-loaded troops to the beach. During April and May 1943, the I Marine Amphibious Corps tested the ability of LVT-1 Alligators to sustain a 10-foot plunging surf and negotiate a coral reef near New Caledonia. The vehicles took a beating but proved their survivability.
It was reassuring to know that the LVTs had sufficient traction and buoyancy to undertake a long ship-to-shore assault over a reef, but the 2d Marine Division only had 75 serviceable Alligators after the Guadalcanal campaign. Julian Smith learned that 100 new LVT-2 Water Buffaloes were sitting on a pier in San Diego and sent an urgent request through the Pacific chain of command that the assault vehicles be shipped to the 2d Marine Division for Tarawa. He was promised half of them, and the critical question became whether or not they would arrive in the Gilberts in time for D-day.
For all its sudden abundance of new carriers and battleships, the Fifth Fleet was still critically short of two new specialized amphibious ships: the tank landing ship (LST), and the revolutionary dock landing ship (LSD).5
LSTs were flat-bottomed, shallow-draft, rough-riding vessels with large bow doors for unloading tanks or LVTs directly onto a beach or atop a reef. LSDs could ballast down at sea, virtually "squatting" in order to flood their well decks in the stern, thereby floating a number of landing boats preloaded with medium tanks and dispatching them toward the beach via a lowered stern gate. The U.S. Navy commissioned the USS Ashland (LSD-1) in early August 1943. Her eventual appearance at Tarawa, laden with 14 M4A2 Sherman tanks, would constitute one of the battle's turning points.
Before the LSD revolutionized the delivery of Sherman tanks, the Marines and Navy had to lift each 34-ton vehicle by a swinging crane from a transport onto a small boat while it was bobbing alongside. The process was so dangerous and time-consuming that the 3d Marine Division, lacking an LSD at Bougainville, chose to leave their valuable Shermans behind rather than expose the naval task force to Japanese air attacks due to inordinate unloading time at anchor near the beachhead.
Critical material delays adversely affected amphibious training and proved nearly fatal to the actual assault. The Southern Attack Force and the 2d Marine Division would pay a price for having neither the opportunity nor the time to fully train their men. Regrettably, the first time the Southern Attack Force would attempt to coordinate the whole mix of naval gunfire, carrier-based air support, and the command and control of an unduly complex 6-hour, ship-to-shore movement would take place under heavy fire on D-day, 20 November 1943.
The Japanese in the Gilberts
Rear Admiral Keiji Shibasaki, Imperial Japanese Navy, took command of the 3d Base Defense Force in the Gilberts on 20 July, exactly four months before the U.S. landings at Tarawa and Makin. A farmer's son from Hyogo Prefecture, Shibasaki was a 28-year naval veteran, including a year as chief staff officer of the Shanghai Special Landing Force. He knew amphibious operations and defensive fortifications. From his headquarters on Betio, Shibasaki commanded garrisons within Tarawa, Makin, and Apamama atolls, in addition to Ocean and Nauru islands, west of the Gilberts. The 49-year-old commander realized that Betio, with its bomber strip, represented the likeliest objective of any U.S. offensive in the Central Pacific.
In August 1942, U.S. Marine Raiders had launched a two-day, dagger-thrust raid on Butaritari Island in Makin Atoll that alerted Imperial Japanese Headquarters to the vulnerability of their outposts in the Gilberts. Immediately, the Japanese began a 15-month concentrated effort to transform Betio into a formidable citadel. The low-lying island—less than 300 acres of sand, coral, and palm trees—was hardly the natural fortress that Peleliu and Iwo Jima would later present. Nevertheless, Japanese construction troops first built the airfield and then surrounded it with 500 bunkers, pillboxes, and gun emplacements. Shibasaki's armament ranged from 13-mm heavy machine guns to 8-inch coast defense guns. Many large-caliber antiaircraft weapons would serve effectively as rapid-firing antiboat guns. A coconut-log seawall, slotted for machine-gun positions, guarded the shoreline. Mines and underwater obstacles protected most of the beaches.
In 1955, historians Philip A. Crowl and Edmund G. Love, veterans of World War II and members of the U.S. Army's historical staff, described Tarawa as "the most heavily defended atoll that would ever be invaded by Allied forces in the Pacific. With the possible exception of Iwo Jima, its beaches were better protected against a landing force than any encountered in any theater of war throughout World War II."6
Shibasaki recognized the strengths of Betio's defenses. Seeking to bolster the morale of his 5,000 rikusentai and armed construction troops, he claimed that "a million Americans could not take Betio in a hundred years." Shibasaki's personal perspective was more realistic. All he had to do was resist an American attack for three days, enough time for the Japanese Combined Fleet to arrive from Truk—1,300 miles away—to sweep the seas clean of the invasion force.
The legendary Japanese naval warrior Isoroku Yamamoto was dead, shot down over the northern Solomons by U.S. P-38 pilots seven months before the battle for Tarawa Atoll. His replacement as commander-in-chief of the Japanese Combined Fleet was 58-year-old Admiral Mineichi Koga—taciturn, competent, and a 37-year veteran. While Koga lacked Yamamoto's strategic vision, he commanded the Pacific war's most formidable fleet, flying his flag from the enormous battleship Musashi in Truk Harbor. In an eerie coincidence, his stern face appeared on the cover of Time magazine two weeks before Tarawa.7
With recent reports of large American task forces departing New Zealand and Hawaii for unknown destinations, Koga, the former chief of the Imperial Japanese Navy's intelligence division, could not dispel Tokyo's misguided belief that the landing of two U.S. divisions at Bougainville on 1 November represented the last enemy offensive of the year.
The Element of Surprise
To avoid detection by the Japanese for as long as possible, Admiral Spruance and the U.S. Fifth Fleet used strict operational security, dispersion, and radio silence to sortie from many different ports and to converge on the Gilbert Islands.8 By the time Japanese reconnaissance aircraft discovered Admiral Pownall's vanguard carriers on 18 November, the Fifth Fleet had already penetrated the Gilberts, attaining strategic surprise. With a sinking heart, Koga knew that this unexpected invasion had come at the worst possible time for his Combined Fleet.
Just two weeks earlier, Imperial Japanese Headquarters had shortsightedly fragmented Koga's fleet by ordering a cruiser task force and most of his veteran flight crews to Rabaul to counterattack the Bougainville beachhead in what would become a disaster for the Japanese. Admiral William F. "Bull" Halsey struck first, surprising the Japanese forces concentrated at Rabaul with a pair of pre-emptive air strikes that damaged eight warships, and—more significantly—downed 121 of Koga's 173 aircraft.
The loss of so many veteran pilots crippled Koga's ability to engage an American fleet in the long-sought decisive naval battle that could reverse the tides of war. Now he would not risk his carriers by steaming into battle with green replacement aviators or deploy his battleships without the protection of the carriers. Halsey's little-known, high-risk carrier raids heralded the first critical turning point in the ensuing battle for Tarawa.
1. 2d Marine Division D-3 Journal for 20 November 1943, D-Day at Betio. Records now held in National Archives and Records Administration, College Park, MD.
2. Grace P. Hayes, The History of the Joint Chiefs of Staff in World War II: The War Against Japan (Annapolis, MD: Naval Institute Press, 1982), p. 409.
3. Hayes, Joint Chiefs, pp. 422—23.
4. Joint Planning Staff 205, "Operations Against the Marshall Islands," 10 June 1943, p. 2.
5. Amphibious landing ships and assault craft in WW II bore a confusing similarity of acronyms. LVTs (landing vehicle, tracked) and LCVPs (landing craft, vehicle, personnel—also called Higgins boats) were the primary ship-to-shore craft, while LSTs (landing ship tank) and LSDs (landing ship dock) were the specialized ships that launched the craft.
6. Philip A. Crowl and Edmund G. Love, Seizure of the Gilberts and Marshalls, a volume in the series United States Army in World War II: The War in the Pacific (Washington, DC: Office of the Chief of Military History, U.S. Army, 1955), p. 74.
7. Time magazine, 8 November 1943.
8. Strategic surprise made possible the successful U.S. landings at Guadalcanal, Tulagi, Bougainville, Tarawa, and Saipan in the Pacific War. Tactical surprise facilitated the rapid, low-cost seizure of Tinian in 1944.